Boiler blow-off apparatus



Dec. 1, 1936. A. KIRCHHOFER ET AL BOILER BLOWOFF APPARATUS Filed Jan. 10, 1954 Patented Dec. 1, 1936 BOILER BLOW-OFF APPARATUS August Kirchhofer, Nashville, Tenn., and William A. Kline, Columbus, Ga.

Application January 10, 1934, Serial No. 705,988

6 Claims. (01. 122-382) Our invention relates in general to the cleaning of boilers, more especially locomotive boilers, and has particular reference to an improved blow-off device whereby sludge, sediment, scale, scaleforming substances, in suspension or solution in the boiler water, may be continuously removed from a boiler.

An important object of our invention is to provide a continuously operating blow-off device of the character described.

Another object is to provide a simple condenser means especially adapted for use in conjunction with a boiler blow-off device.

Another object resides in providing for the mixing of air with the steam discharged by a blow-off device in order to prevent the ejection of steam clouds into the atmosphere which impair visibility, and/or to reduce the velocity and pressure of the discharged steam.

Another important object is to provide a boiler blow-01f device wherein the heat contained in the discharged steam is conserved.

Another important object of the invention resides in reducing the velocity of the vapors discharged by a blow-off device, so that the same may be discharged into the ash pit without disturbing the contents of the pit, a further object being to discharge the vapors safely into the ash pit of the boiler furnace in such a way that the heated vapors may rise through the furnace grate and again be applied in heating the boiler.

Another object is to provide a condenser of simple, rugged, and inexpensive construction, particularly well adapted for use in conjunction with a boiler blow-off device.

. Another important object is to provide a device of the character described which is adapted for continuous operation.

Another important object resides in providing a blow-off device embodying a strainer of novel construction whereby to separate the sludge,

bodiment of the invention.

Referring to the drawing:

Figure 1 is a fragmentary side view of a locomotive having a boiler provided with devices embodying our present invention;

Figure 2 is a sectional view taken substantially along the line 22 in Figure 1;

Figure 3 is an enlarged sectional view taken substantially along the line 33 in Figure 2.

To illustrate our invention, we have shown on the drawing, a locomotive ll having a boiler l3 and a furnace l5, said boiler having water legs I! extending along the opposite sides of the furnace. Beneath the furnace extends a shell l9 forming an ash pit. The shell I9 may have small openings therethrough as shown at I901. in Figure 2. A blow-off device 2| is connected on the wall of the boiler preferably at or near the lower end of one of the water legs I1 and comprises a blow-off cook 23 through which boiler water containing slag, scale and other impurities may be ejected from the boiler to a strainer 25, in which the water is separated from the impurities, the water being conducted through a choke fitting 21 wherein it is transformed into steam and then into a condenser 29 from which the condensed steam at low pressure is delivered through a suitable conduit or pipe 3i, the outer end of which is or may be belled as at 32 into an ash pit beneath the boiler furnace.

The strainer 25, in addition to the water outlet to the choke fitting 21, has a valved sludge and scale outlet through which the separated impurities may be discharged into the ash pit. In addition, the strainer has an outlet 35 through which any moisture within the strainer may escape through a suitable drain valve 38 so that the strainer will at all times be in substantially dry condition to thus eliminate the danger of freezing should the device be permitted to stand inoperative and exposed to freezing temperatures.

The blow-off cock 23 preferably comprises an angle valve which may be of standard form comprising a casing having angularly extending legs, one of which communicates with the interior of the boiler and carries a valve stem. The inner end of this valve stem is operatively connected with a valve located in said leg, the other end of the stem extending outside of the casing and carrying a manually controllable valve-operating handle 31. The other leg of the casing extends preferably at right angles to the leg containing the valve stem and is connected as by means of a gland 39 with a pipe 4| leading to the strainer 25.

The strainer 25 preferably comprises a casing formed as a standard X-fitting, one of the necks 43 of which is connected to the end of the pipe 4| by means of a gland 45, the X-fitting having a neck 41 in line with and facing oppositely from the neck 43. The neck 41 is connected with the sludge clean out pipe 33 by means of a gland 49. The sludge clean-out pipe 33 includes a valve 34 for controlling the discharge of separated sludge from the strainer.

The strainer casing contains a preferably cylindrical member the sides of which are perforated as illustrated in Figure 3. 5i communicates at its opposite ends with the pipes 33 and 4|, being held in place by and between the inner ends of the glands 45 and 49, which are beveled to receive the correspondingly beveled ends of the perforated pipe 5|. In order to clean out accumulated sludge, scale, and the like, at any time, it is only necessary to open the valve 34 and permit pressure in the boiler to blow the collected materials out of the strainer 52 through the pipe 33.

The strainer casing is also formed with a neck 11, which is connected preferably by means of gland 19 to the discharge valve 38, and the casing of the strainer is preferably mounted with the neck 11 facing downwardly so that all moisture in the strainer will fall toward the drain valve 38 and thus be ejected when the device is inoperative. The drain valve is of any suitable form preferably comprising an inwardly opening valve normally spring pressed to open. The spring, however, is not strong enough to resist the boiler pressure so the valve closes when boiler water is being admitted to the casing 25 and opens to permit water to escape as soon as the pressure is cut off. The strainer casing also is formed with a neck 53 preferably in line with and facing oppositely from the neck 11. The neck 53 is connected preferably by means of a gland 55 with one end of a conduit 51 leading to the expansion nozzle 21. The pipe 51 is preferably threaded into the central opening of a T-fitting 59.

The choke fitting or expansion nozzle 21 comprises a cylindrical element having a relatively large bore 6| throughout the major portion of its length and a restricted orifice 63 forming a nipple at one end and this nippled end is secured as by threading into one of the aligned openings of the T-fitting, the other aligned opening of the T-fitting being closed by means of a stopper 66, which is preferably threaded into the fitting. By simply removing the stopper 56, the restricted bore of the nipple 63 may be quickly cleaned of accumulated dirt.

The end of the choke fitting, remote from the nipple portion 63, is connected as by threading into one end of a connector pipe 65, the other end of which is connected to the condenser 29. The condenser 29 preferably comprises a tubular casing 61 which may be a pipe of suitable size and connected at one end to the discharge pipe 3!. If desired, the casing 61 may be formed integral with and as a continuation of the pipe 3|. The end of the casing 61 opposite from the discharge pipe 3! is closed as by means of a disk 69, the edges of which are welded or otherwise secured to the ends of the pipe forming the casing 31. The disk 69 is perforated to receive a pipe 1|, forming a nozzle 13 opening into the interior of the casing 61, said pipe 1| being welded or otherwise secured to the disk 69 and having an end projecting out of the condenser and connected as by threading to the connector pipe 65. The casing 61 is also provided with a plurality of openings 15 preferably disposed circularly in the end of the casing behind the nozzle 13.

The blow-off device of our present invention is adapted to operate continuously, that is to say, when the boiler is in operation, the valve 23 may The member be opened and left in open position to continuously deliver water and solid impurities from the boiler into the interior of the cylindrical strainer element 5|, the blow-off cock being connected with the boiler substantially at a point where scale, sludge and other impurities become concentrated. The impurities delivered to the strainer element 5| are retained therein while the water escapes through the perforations and through the pipe 51 thence through the restricted orifice 63 wherein it is transformed into steam by pressure reduction. The orifice operates to limit the amount of steam which can be blown 01f through the device. After it passes the orifice 63, the steam expands and reduces pressure as it passes through the connector pipe 65 and is still further reduced in pressure when it enters the condenser 61. The fiow of steam through the nozzle 13 creates a suction in the chamber 61 behind the nozzle which causes air at relatively low temperatures to be drawn into the condenser casing through the opening 15. The orifice 63 is of such size and the openings 15 are of such size and number that sufficient air is drawn into the condenser 61 to condense all of the steam entering the condenser so that water and warm air only are ejected through the pipe 3| into the ash pit. The water so ejected keeps the ashes damp, which is a desirable feature, while the warm air is delivered through the grate into the furnace so that none of the heat contained in the steam blown off through our device is wasted but the warm air mingles with theproducts of combustion in the furnace and aids in the heating of the boiler. not vaporized by the ashes in the ash pit will drain from the pit through openings I901).

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction, and arrangement of the several parts without departing from the spirit or scope of our invention or sacrificing any of its attendant advantages; the form herein described being Excess water a preferred embodiment for the purpose of ilaligned openings on its opposite sides and a water outlet intermediate said openings, one of said aligned openings comprising an inlet for water and impurities, means connecting the inlet to the boiler, the other aligned opening comprising an outlet for solid impurities, a drain pipe connected to said last named outlet, a foraminous screen extending in said casing between said aligned openings, the interior of said casing communicating with said aligned openings and the foraminous walls of said screen being exposed to said intermediate water outlet whereby water introduced into said foraminous element may escape through the foraminations thereof and thence through the intermediate outlet while the solid impurities remain trapped in the foraminous element, and valve means for controlling flow through said alined openings.

2. The combination with means forming a boiler blow-01f device, including a strainer adapt-,

ed to receive water and solid impurities from the boiler and to separate the water from the impurities, of means forming a condenser adapted to receive water from the strainer and reduce any steam therein to Water comprising a cylindrical casing communicating at one end with the atmosphere, a nozzle extending in its opposite end axially through which water and steam from the strainer may be introduced into the casing and blown therethrough towards its opposite end in order to create a suction in the end of the casing adjacent the nozzle, and openings in the casing in the nozzle end whereby to draw cold air into the casing for the purpose of condensing the steam therein.

3. A boiler blow-off device comprising a separator, means for delivering boiler solution to the separator, a discharge for the separator and a condenser in the discharge, said condenser comprising a relatively large tubular member forming a casing having an exhaust outlet opening to the atmosphere at one end and an inlet nozzle comprising a relatively smaller tubular element extending into the other end of the casing, said nozzle having an orifice directed toward the exhaust outlet, said end of the casing being formed with means permitting the introduction of air into the casing behind said nozzle orifice whereby when fiuids to be condensed are introduced through said nozzle into said casing under pressure a suction will be produced in the casing behind said nozzle for the purpose of drawing air into the said casing through the air inlet.

4. In combination with a pressure boiler for a locomotive, a blow-off apparatus comprising a separator for separating boiler water from impurities contained therein, means for delivering water containing impurities from said boiler to said separator, means for delivering cleansed water from said separator and for reducing the pressure of said water to form steam, a condenser for receiving steam from said delivering means and for mixing air therewith to condense the steam into water, a fire box, an ash pit disposed beneath said fire box, and means for delivering the mixture of air and water to said ash pit.

5. A blow-01f device for a boiler comprising a conduit adapted to be operatively connected to a boiler to receive hot boiler water and solid impurities, a chamber in said conduit, a strainer in said chamber to separate water from the solids, an outlet conduit normally closed for forming an outlet from the chamber for the solids, a second outlet conduit having a restricted orifice therein and providing an outlet for the water, said restricted orifice providing pressure reducing means whereby the heated water passing through the orifice. may be converted into steam, a condenser operatively connected to the outlet of said second conduit for condensing the steam, said condenser being provided with a plurality of air inlets to facilitate the condensation, and a normally open drain valve for said chamber.

6. A blow-off device for a boiler comprising a conduit adapted to be operatively connected to a boiler to receive hot boiler water and solid impurities, a chamber in said conduit, a cylindrical strainer in said chamber to separate water from the solids, an outlet conduit normally closed and operatively connected to the interior of the strainer for forming an outlet for the solids, a second outlet conduit having a restricted orifice therein and providing an outlet for the water, said restricted orifice providing pressure reducing means for converting the heated Water passing through the orifice into steam, a condenser connected to the outlet of said second conduit for condensing the steam, said condenser being provided with a plurality of air inlets to facilitate the condensation, and a drain in said chamber having a valve normally open but being adapted to be closed by pressure of the water in the conduit.

AUGUST KIRCHHOFER. WILLIAM A. KLINE. 

